Verfahren und Vorrichtung zur Durchflussregelung

摘要

A metering apparatus, which may be single- or double-acting, includes a valve device including a closure member 21, an inlet port 2, an outlet port 4 and one or two other ports (6,7) communicating with a metering chamber of the single-acting apparatus or respective metering chambers 14 of the double-acting apparatus. The closure member 21 prevents oommunication between the inlet port 2 and the outlet port 4 during normal working, but, to allow flushing of the apparatus by cleaning fluid, the closure member 21 can be displaced to an abnormal position in which the inlet port 2 communicates with the outlet port 4 by way of the other port(s) (6,7).